Multipart core



Aug. 16, 1927. 1,638,846

M. GUYOT.

MULTIPART GORE Filed Feb. 29, 1924 2 Sheets-Sheet 1 INVENTOR TTORNEYSA118. 1927- M. GUYOT MULTIPART CORE Filed Feb. 29. 1924 2 Sheets-Sheet 2MW B.

Patented Aug. 16, 1927.

UNITED STATES PATENT OFFICE.

MARIUS GUYOT, OF CLEVELAND, OHIO,

ASSIGNOB '10 ALUMINUM COMPANY OF AMERICA, OF PITTSBURGH, PENNSYLVANIA, ACORPORATION 01' PENNSYLVANIA.

MULTIPABT CORE.

Application filed February 20, 1924. Serial Io. 695,902.

-.inwardly extending annular projection at the open end thereof.

The principal object of my invention is to construct a new and improvedmultipart core for cup shaped castings having an enlargedcircumferentially extending inwardly projecting flange adjacent to theopen end thereof.

Other objects will appear and will be pointed out hereinafter and setforth in the claims.

Prior to my invention it has not been possible, so far as I am aware, tomake cup shaped castings, and particularly piston castings, having at ornear the open end thereof annular projections or'flanges, thedimensionsof which radially of the casting were comparatively large, theexact size within a certain range being independent of the extent towhich certain of the outer core sections could be moved inwardly of thecasting after the center section had beenremoved from the casting, thesize and location of the bosses and the minimum permissible size of thesaid outer sections, it being understood that such sections tend to warpin use if smaller in cross section than certain permissible sizes.

By my invention, however, I- am able to construct a core, the parts ofwhich have dimensions larger than those of minimum size permissible forcommercial purposes, and the core being capable of forming relativelylarge flanges, when measured radially of the casting, at or adjacent tothe open end of the casting, as compared with flanges obtainableheretofore. I am able to accomplish these objects within a wide range-.0sizes, shapes and locations of the bosses. A core capable ofaccomplishing these objects and embodying my invention is hereinafterdescribed.

In .the drawings accompanying this specification and forming a partthereof:

Figurel isa fragmentary vertical cross sectionalyview through a mold fora piston casting provided with a core embodying my iDVBIltlOIlQ Figure'2is a fragmentary cross sectional view taken on line 22 of Fig. 1.

Figure 3 is a fragmentary cross sectional" view similar to Fig. l butshowing the center core section removed and one of the side coresections partly removed from the castmg.

Figures 4 and 5 are respectively fragmentary cross sectional views takenon lines 44 and 5-5 respectively of Fig. 1.

Figure 6 is a perspective view of one of the outer core sectionsembodying my invention, and

Figure 7 is a perspective view of the center core section of my improvedcore.

In describing my invention I have elected to discloseit in connectionwith a conventional form of permanent mold for a cup shaped castingof'the piston type. Since these molds are not only shown in U. S.Letters Patent 1,296,588 issued March 4, 1919, to J. H. Bamberg but arealso well known to those skilled in the art, only sufficient portionsthereof have been shown in the drawings attached to this specificationto render clear and understandable the cooperation thereof with myimproved core. For more complete disclosure of the mold itself whichforms no part of my present invention reference may be had to the patentmentioned.

The mold, which I. have shown, comprises a base 1, side mold members 2,cooperating with each other and the base to form between the meetingfaces thereof a casting cavity 3 for forming a piston casting. Core pins4 project through the mold members 2 and extend into the casting cavity3 to form ,hollow bosses 5 on the piston casting.

multipart core 6 consisting of seven parts extend into the castingcavity 3, the outer surface of the assembled core forming the f 5 innerend and side walls of the casting cavity 3. The assembled core issupported in the casting cavity by laterally extending flanges 7 on theupper or outer end of certain of the sections to seat on the top surfaceof the mold halves 2 and by similar flanges 8 on the center core sectionadapted to seat on certain of the other sections. When the assembledcore 6 is supported on the mold halves 2 as shown in Figures 1 and 2 andcore pins 4 are inserted, molten metal may be led into the castingcavity 3 through any suitable gate 2) (Fig. 5) to fill the cavity. Asthe metal therein solidifies the core pins and the main core sectionsare withdrawn after which the mold halves 2 may be separated and thecasting removed from the mold.

Since my present invention relates more particularly to theconfiguration of the multipart core, 1 will describe it in some detail.

I preferably form the core 6 in seven parts comprising a center or innersection and six outer sections surrounding the same wlth one section oneach of the narrow edges of the center section and two sections on eachof the wider side surfaces. The center-section 10 which is substantiallyrectangular in cross section has its opposite, narrow sides or edges 1t)provided with substantially uniform recesses 1U extending from end toend and its wider sides 10 provided With wedge shaped recesses ltlvarying in width from a maximum at the inner end to a minimum at theouter end. Outer sections 11 which are of approximately the same widthas the greatest width of the center section 10 are provided with innersurfaces shaped to cooperate with the edges 10 and recesses 10 of centersection 10. These three sections 10 and 11 when assembled constitute arow of sections of about the same width across the center of the core.()n opposite sides of the row of sections formed by sections 10 and 11are positioned pairs of sections 12, each pair having-their innersurfaces formed with raised upwardly tapered portions 12 to engage withthe longitudinally extending recesses 10 of the center section 10 andflat surfaces 12" to engage with the adjacent side surfaces 10 ofsection 10 and 11 of sections 11. Each pair of sections 12 have theirmeeting faces recessed to provide cavities 13 in which inwardlyextending wrist pin bosses 5 in the casting may be formed. The assembledcore thus comprises two pairs ott' oppositely disposed sections 12between which is located a row of sections comprising sections 10 and12.

In addition to the boss recesses 13 formed in the outer surfaces of theassembled core I provide near the outer or open end of the castingcavity a circumt'erentially extending recess 14 which is formed in theouter surface of the core to provide an inwardly extending annular orcircumferential flange 15 at or adjacent to on the open end of thetasting. The inner end of the assembled core may, if desired, besuitable recessed as at 16 to provide a rib 17 connecting the two bossesand the head of the casting. Additional cross ribs may be similarlyformed if desired by merely recessing the core as may be understood bythose skilled in the art.

In assembling the core in the mold preliminary to making the casting thepairs of side sections 12 are inserted into the casting cavity so thatthe flanges 6 rest upon the top of mold halves 2. Sections 11 areinserted so that the corresponding flanges 7 rest on mold halves 2 andthe sections occupy substantially the position shown in Figures 4 and 5.Then section 10 is inserted between the outer sections and forced downinto the position shown in Figure 2.

The recesses 10 prevent lateral movement of sections 11 relative theretowhile tapered recesses 10 not only prevent lateral movement of sections12 relative thereto but also serves to lock sections 12 together,thereby forming a compact core, with parts held in assembled position inthe mold in a manner to resistfn'iechanica-l displacement or warping ofthe thinner sections.

After the molten metal has filled the casting cavity and solidified andthe sections are ready to be removed, the center section 10 is firstwithdrawn, then sections 11 are moved inwardly at the bottom and tiltedin at the top sufliciently to'clear the inwardly projection 15 on thecasting and then Withdrawn substantially longitudinally from thecasting. Next the sections 12 are removed by rotating the same away fromthe bosses on the casting, moving the lower or inner ends slightlyinward and tilting the upper or outer end of the core sections untilthey approach or contact with the opposite pair of sections 12 afterwhich the section may be withdrawn from the casting by a slightrotational motion to clear completely the bosses and projection 15 andthen longitudinally out of the casting. The remaining pair of sections12 are removed in a similar manner.

It. will be observed that the longitudinal recesses 10" on centersection 10 tend to prevent side movement of sections 11 with respect tothe center section 10 especially when the assembled sections are clampedin a mold preliminary to or during the casting.

Likewise the lfinfl'ltlltllllfll recesses 10 of the center section ll)prevent relative sidewise movement of the sections 12 with respect tothe center section 10 and furthermore due to the upward tapering ofthese recesses 10 each pair of sections 12 may be tightly wedgedtogether. The center section thus prevents relative sidewise movement ofall of the outer core sections with respect to the center section 10 andin addition assists in bringing the pairs of side sections 12 into closeoperative position and maintaining them in such position during thecasting. It will further "be observed that the recesses 10 and raisedportions 12 of sections 12 permits ready removal of the core section it)from the assembled core and consequent collapse and easy removal of theremaining core sections from a casting. When center casting, comprisingsix section 10 is removed side sections 11 may be moved inwardly at thebottom a short distance until they contact with raised por' "011 12 onside sections 12 but the top may be tilted toward the core center untilit strikes along the length of the inclined surface'of raised portion12. Such tilting is sufficient to clear the sectionsfrom projectingflange 15 on the casting and permit withdrawal of the section from thecasting. In this manner I am able to cast a cup-shaped article having anenlarged inwardly extending circumferential projection adjacent its openend, without being limited to certain sizes, shapes, and locations ofthe bosses and without conflict with the minimum permissible sizes ofthe outer core sections.

Having thus described my invention, what I desire to secure by LettersPatent is defined in what is claimed, it being understood that changesor alterations of the structure claimed and not amounting to inventionare within the limits of my invention.

What is claimed is:

1. A new and improved multipart core, for a cup shaped casting having aninwardly directed circumferentially extending flange adjacent to theopen end thereof which comprlses a center core section havinglongitudinally recessed side surfaces, the said recesses of two oppositesides gradually decreasing in width from the inner ends of the sectionto the outer end thereof and also from the outer side of the sectioninwardly thereof, and outer core sections surrounding the said centersection and having raised portions corresponding to and seating in thesaid recesses when the core arts are assembled, the assembled coresectlons having an annular recess in their outer surfaces to form aninwardly extending projection on the cast- 1n A multipart core, for aflanged piston exterior sections having an annular recess in the outersurfaces thereof, two opposite pairs of the said sections having bossrecesses formed therein, and an interior section having surfaceengagement with each of the outer sections, each surface of the saidinterior section lying adjacent to the said two pairs of seetions beingprovided with a recess having side walls converging toward the outer endof the sections and inclined at an obtuse angle to the inner wall of therecess. the said two opposite pairs of sections having raised portionscorresponding to and adapted to seat in the said recesses.

3. A seven part core comprising a center section having fourlongitudinally recessed surfaces, two outer sections each engaging oneof the said recessed surfaces, and a pair of outer sections engagingeach ofthe remaining oppositely disposed recessed surfaces, each saidpairs of sections having a raised, laterally and longitudinallytapering, wedge shaped portion extending longitudinally thereof, eachpair having meeting faces recessed to form a boss, and the assembledcore having an annular recess in the outer surface remote from the innerend. thereof.

4. A seven piece core comprising a center section having two oppositeside surfaces each provided with a longitudinally extending, laterallyand longitudinally tapering, wedge shaped recess and twooppositelydisposed edge surfaces two outer sections, each substantiallyas wide as the eatestiwidth. of the said center section an? disposed onopposite sides of the center section and'engaging the said edgesurfaces; and a pair of outer sections arranged on either side of thesaid center section and enga ing with the said wedge shaped recess anthe adjacent sides of the said two outer sections.

.5. A seven piece core comprising a center section having two oppositeside surfaces each provided with a longitudinally extending wedge shapedrecess and two oppositely disposed edge surfaces; the said wedge shapedrecesses each having sidewalls converging inwardly and alsolongitudinally of the section two outer sections, each substan-. tiallyas wide as the greatest width of the said center section and disposed onopposite sides of the center section and engaglng the said edgesurfaces; and a pair of outer sections arranged on either side of thesaid center section and engaging'with the said wedge shaped recess andthe adjacent sides of the said two outer sections, the assembled outersections having a clrcumferen-

